Study On The Level Of Serum Brain-derived Neurotrophic Factor And Its Correlation With Cognition In Patients With Alzheimer’s Disease

Objective:Among the existing research results,the exact relationship between the level of brain derived neurotrophin(BDNF)in peripheral blood and Alzheimer’s disease(AD)cannot be determined.This study explored the changes of serum brain-derived neurotrophin levels in AD patients before and after treatment,and explored the relationship between these changes and cognitive function.Methods:From September 2020 to September 2021,40 patients with Alzheimer’s disease who visited the Qingdao Mental Health Center,Linyi Mental Health Center(Linyi Fourth People’s Hospital)and were hospitalized in the geriatric department were selected as the study group,while 40 healthy volunteers(samples from Linyi Mental Health Center/Linyi Fourth People’s Hospital Health Examination Center)in the same period were selected as the control group,aged between 50 and 90 years.Both the study group and the control group received the assessment of MMSE(Simplified Mental State Assessment Scale)to assess the cognitive function of the patients when they were enrolled,and 5ml of blood was extracted from the peripheral vein in the morning of the next day and frozen for storage.After that,enzyme linked immunosorbent assay(ELISA)was used to determine the level of brain derived neurotrophic factor in the sample serum.After 12 weeks of treatment with medication(memantine,starting at 5mg/day,increasing by 5mg/day per week,gradually increasing to the maximum dose of 20mg/day),cognitive function was assessed again using MMSE,and serum BDNF levels were measured again using the above methods.Correlation analysis was performed on the serum BDNF levels,course of disease,age,and MMSE scores of patients in the study group.Results:1.Demographic characteristics such as gender ratio,age range,and level of education were not different between the control and Alzheimer’s disease groups(P>0.05).2.The serum BDNF level(ng/ml)in the study group was lower than that in the control group,with a significant difference(P<0.05),which was statistically significant.3.After 12 weeks of treatment,the level of serum BDNF in patients with Alzheimer’s disease was significantly increased,learning,memory and other functions were enhanced,and MMSE scores were significantly improved compared with those before treatment(P<0.05).4.The more serious the disease was,the longer the course was,and the lower the serum BDNF level was in the study group(P<0.05);The higher the MMSE score,the higher the serum BDNF level(P<0.05)Conclusion:1.The level of serum brain-derived neurotrophin in patients with Alzheimer’s disease was lower than that in healthy controls.2.After treatment,the level of serum brain-derived neurotrophin in patients with Alzheimer’s disease has increased,and the cognitive function has improved.3.The level of serum brain-derived neurotrophin in patients with Alzheimer’s disease before and after treatment was significantly negatively correlated with the course of disease,age,and severity of the patients,but positively correlated with the score of the Simple Intelligence State Examination Scale.The above shows that the level of serum brain-derived neurotrophin is positively correlated with the level of learning,memory and other cognitive functions of patients with Alzheimer’s disease;Clinically,we can predict the severity of the patient’s condition and the improvement after treatment by measuring the level of serum brain derived neurotrophin,so as to guide clinical diagnosis and treatment.